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1.
【目的】本研究旨在鉴定灰飞虱Laodelphax striatellus中的IκB激酶(IκB kinase,IKK)相关基因,并调查其在灰飞虱抗病毒中的作用,以进一步深入理解传毒介体应对植物病毒的先天免疫机制。【方法】通过生物信息学鉴定了灰飞虱基因组中IKK相关基因;以无毒及水稻条纹病毒(rice stripe virus,RSV)侵染的灰飞虱为材料,利用RT-PCR方法检测IKK相关基因在无毒灰飞虱各个龄期(卵、1-5龄若虫、雄成虫和雌成虫)及成虫不同组织(肠道、唾液腺、血淋巴、脂肪体、卵巢和精巢)中的表达量;利用qRT-PCR方法检测无毒以及RSV侵染后的灰飞虱IKK相关基因在各个龄期及成虫不同组织中的表达量;通过对3龄若虫注射IKK基因dsRNA进行RNA干扰后,利用qRT-PCR检测带毒灰飞虱中表示病毒含量的RSV外壳蛋白(CP)基因转录水平。【结果】在灰飞虱基因组中鉴定到了两个IKK相关基因即IKKα(GenBank登录号:MK903504)和TANK结合激酶1(TANK-binding kinase1)基因TBK 1(GenBank登录号:MN124506)。IKKα开放阅读框长2379 bp,编码792个氨基酸;TBK 1开放阅读框长1551 bp,编码516个氨基酸。两个基因编码的蛋白都具有1个保守的丝氨酸/苏氨酸激酶结构域和1个泛素折叠结构域。RT-PCR结果表明,IKKα和TBK 1在无毒灰飞虱各个龄期及成虫不同组织中均有表达。qRT-PCR分析结果表明,IKKα和TBK 1在RSV侵染后的灰飞虱各个龄期及成虫不同组织中的表达水平与其在无毒灰飞虱中的表达量之间存在明显差异。进一步将RSV侵染后的灰飞虱3龄若虫中的IKKα和TBK 1干扰后,带毒灰飞虱中的RSV含量显著上升。【结论】本研究结果表明,NF-κB信号途径中的两个重要基因IKKα和TBK 1在灰飞虱中广泛表达,且在灰飞虱抵御RSV的侵入过程中可能具有重要功能。这些结果为今后进一步深入研究NF-κB免疫通路在灰飞虱抗病毒中的功能提供了丰富的基础信息。  相似文献   
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2004年10月,由三代植物学家历时45年完成了《中国植物志》。7年之后,中国植物学会系统与进化植物学专业委员会和云南省植物学会在昆明举办了201l全国系统与进化植物学研讨会暨第十届青年研讨会。会议明确提出了“后植物志时代的系统与进化植物学”这一主题。2013年9月,英文和修订版《中国植物志》联合编委会在北京宣布,世界上最大和高水平的FloraofChina已全面完成,  相似文献   
4.
Tumor necrosis factor (TNF) and the TNF receptor (TNFR) superfamily play very important roles for cell death as well as normal immune regulation. Previous studies have strongly suggested that c-Jun N-terminal kinase (JNK) signaling pathway plays a critical role in ischemic brain injury. The purpose of this investigation was to examine the protective effect of remifentanil preconditioning in cerebral ischemia/reperfusion injury (CIR) and its possible molecular mechanism. Results showed that Remifentanil pretreatment significantly decreased the CD4+ and increased the CD8+ in cerebral tissues. Additionally, CD4+/CD8+ in CIR + Remifentanil group was markedly lower than that in CIR group. TNF-α and TNFR1 in CIR + Remifentanil group rats was found to be significant lower than that in CIR group rats. The expression levels of Cyt-c, caspase-3, caspase-9 and pJNK proteins in brain of CIR + Remifentanil group rats were found to significantly decreased compared to CIR group rats. In addition, decreased ROS level indirectly inhibit JNK activation and cell death in CIR rat receiving Remifentanil preconditioning. From current experiment results, at least two signal pathways involve into the process of Remifentanil preconditioning inhibiting cerebral damage induced by ischemia reperfusion. The inhibitory effects of Remifentanil preconditioning on the brain damage are achieved probably through blocking the activation of TNF-α/TNFR1, JNK signal transduction pathways, which implies that Remifentanil preconditioning may be a potential and effective way for prevention of the ischemic/reperfusion injury through the suppression extrinsic apoptotic signal pathway induced by TNF-α/TNFR1, JNK signal pathways. Taken together, this study indicated that regulation of the TNF-α/TNFR1 and JNK signal pathways may provide a new therapy for cerebral damage induced by ischemia and reperfusion.  相似文献   
5.
水稻非生物胁迫相关QTL研究进展   总被引:1,自引:0,他引:1  
培育优质高产水稻品种是水稻育种工作者的首要目标。近年来,不断恶化的环境条件使水稻生长面,临更多的逆境胁迫。其中,非生物胁迫严重影响水稻产量提高和品质改善。从QTL角度研究水稻对非生物胁迫的适应机理,对于提高水稻产量、品质和抗逆性等方面具有重要的意义。本文综述了近年来水稻非生物胁迫相关QTL的研究进展,以及通过分子辅助育种手段创制多目标性状聚合的优良水稻品种的主要策略,为实现水稻优质高产和广适性的综合改良提供思路。  相似文献   
6.
为了了解菊黄东方鲀(Takifugu flavidus)、暗纹东方鲀(T.obscurus)及其杂交F1代的肌肉营养特征,利用生物化学方法,从每类实验样本中取9尾对其肌肉中的粗蛋白、粗脂肪、水分、粗灰分和氨基酸成分进行了测定和分析。结果显示:(1)杂交F1代在生长方面具有明显的杂交优势,与亲本之间存在着显著差异(P0.05),杂交F1代的体重为其亲本的1.48~1.77倍;(2)杂交F1代肌肉水分含量与其母本含量相近,但粗脂肪含量均较亲本少(P0.05),粗蛋白含量则与亲本差异不显著(P0.05);(3)除色氨酸和胱氨酸外,16种氨基酸均在肌肉样本中被检测到,除甲硫氨酸外,其余15种氨基酸间含量均存在着显著性差异(P0.05)。菊黄东方鲀(♀)×暗纹东方鲀(♂)杂交F1代的总氨基酸含量最高,而暗纹东方鲀(♀)×菊黄东方鲀(♂)F1代总氨基酸含量则介于两亲本之间。对其必需氨基酸总量进行分析发现,菊黄东方鲀与其正反杂交F1代之间均存在显著性差异(P0.05),而暗纹东方鲀与其正反杂交F1代之间差异不显著(P0.05);(4)肌肉营养品质评价结果表明,菊黄东方鲀(♀)×暗纹东方鲀(♂)杂交F1代的鲜味氨基酸含量为26.68%,明显高于双亲样本(菊黄东方鲀22.28%、暗纹东方鲀25.20%),而暗纹东方鲀(♀)×菊黄东方鲀(♂)F1代的鲜味氨基酸总量(23.30%)较其父本偏高,但低于其母本。研究结果表明,杂交东方鲀的肌肉营养综合了双亲的优良特性,特别是是菊黄东方鲀(♀)×暗纹东方鲀(♂)杂交F1代,拥有最高的鲜味氨基酸含量,具有推广价值。  相似文献   
7.
This study was aimed at studying the effect of the induction of immune tolerance to swine cardiac myosin from anti-L3T4 monoclonal antibody injection and whether the immune tolerance could protect mice with myosin-induced myocarditis from myocardial injury. Twenty-four Balb/c mice were divided into two groups at random. All of the mice were immunized with swine cardiac myosin on the 1st day, 14th, 28th, 42nd, and 52nd day. Immune tolerance was induced by triplicate injections of 400 microg anti-L3T4 McAb on the 0 day (intravenous), 1st day, and 2nd day (intraperitoneal) in McAb-treated group. In the saline-treated group, saline of the same volume as anti-L3T4 monoclonal antibody was used as a control. The sera and hearts biopsies of all mice were collected on the 58th day. The anti-cardiac myosin antibody was examined with ELISA, and pathological changes of heart were observed by light microscope. It was shown that mice immunized with swine cardiac myosin could produce anti-myosin antibody and the anti-cardiac myosin antibody was positive in most of the saline-treated group but negative in the McAb-treated group. Morphologically, myocardial degeneration, necrosis, and infiltration of inflammatory cells were found in the saline-treated group but not in the McAb-treated group. In conclusion, this study indicated that the immune tolerance to cardiac myosin was induced by the anti-L3T4 monoclonal antibody, and accordingly myocardial injury could be prevented by induction of immune tolerance.  相似文献   
8.
Although epidemiological studies have shown that exposure to tobacco smoking significantly increases the risk of bacterial meningitis, heretofore the pathogenic effects of smoking on this disease have been poorly understood. In order to dissect this issue, we have investigated the effects of nicotine, the major component of tobacco, on E. coli invasion of human brain microvascular endothelial cells (HBMEC). Our studies showed that E. coli invasion of HBMEC was significantly enhanced by nicotine in a dose-dependent manner. The nicotine-mediated enhancement was associated with actin cytoskeleton rearrangement and morphological changes in the eukaryotic host cell that are essential for bacterial entry. The recombinant IbeA protein and alpha-bungarotoxin (a nicotinic acetylcholine receptor antagonist) were able to efficiently block the nicotine-mediated cellular effects, suggesting the involvement of the IbeA and nicotinic receptors. Blocking of phosphatidylinositol 3-kinase (PI3K) by LY294002 abolished the entry of E. coli in HBMECs treated with nicotine in a dose-dependent manner. Inhibition of PI3K was associated with decreased phosphorylation of Akt and actin cytoskeletal rearrangement. In contrast to PI3K, blockage of Rho kinase (ROCK) by Y27632 upregulated both nicotine- and E. coli-mediated cellular responses. Thus, this study provides experimental evidence for the first time that the major component of tobacco, nicotine, enhances meningitic E. coli invasion of HBMEC through modulation of cytoskeleton.  相似文献   
9.
草果种植对植物多样性的影响   总被引:1,自引:0,他引:1  
从林下植物物种数、株数、乔木盖度、多样性指数等方面,对种植草果的天然林片断与未种植草果的天然林地的植物进行调查与比较分析,结果发现:(1)不同草果种植时间乔灌木层的盖度在20.0%~50.0%之间变动;(2)随着种植时间的延长,乔灌层植物株数明显下降,乔灌层物种数趋向单一,主要保留旱冬瓜作为草果的遮荫树种;(3)天然林的草本层物种数为13种,草果种植到80年后草本层物种数只有8种;草本层株数在草果种植5年后在48~285株间的波动,远低于种植初期;(4)乔灌层Shannon-Wiener指数在草果种植30年降低到0,但草本层Simpson指数在种植草果半年至一年期间多样性指数较低为0.2266~0.33990。虽然5年后稳定在0.4351~0.8062,但普遍低于天然林(0.7681)。为了维持天然林的可持续性和稳定性,建议草果栽培在人工林下进行。  相似文献   
10.
蛋白质组学关键技术研究进展   总被引:3,自引:0,他引:3  
蛋白质组学是后基因组时代的一门新兴科学,是对生物体在蛋白质水平上定量、动态、整体性的研究。简要综述了高通量蛋白质分离和鉴定技术,如双向电泳、生物质谱、蛋白质芯片、酵母双杂交、同位素亲和标签及生物信息学的原理、方法、应用及存在的问题与局限,并对蛋白质组学研究的发展前景进行了展望。  相似文献   
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